Optical disc having indication portion
US5675570A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Dec 19, 1995 |
| Grant date | Oct 7, 1997 |
| Priority date | — |
| Expiry date | Dec 19, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/26
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical disc is provided with: a disc substrate of light transmissive type having an information record surface including an information recorded region, where pits or grooves carrying an information signal are coaxially or spirally formed, and an information not-recorded region, where the pits or grooves carrying the information signal are not formed; a light reflective layer wholly disposed on the information record surface in the information recorded region, and partially disposed on the information record surface in the information not-recorded region such that an indication pattern is formed of the partially disposed light reflective layer on the information record surface in the information not-recorded region; and a protection layer disposed on the light reflective layer and a portion of the information record surface in the information not-recorded region where the light reflective layer is not disposed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.